Taller but thinner: trends in child anthropometry in Senegal, 1990–2015

OBJECTIVE: To investigate trends in child anthropometry in Senegal between 1990 and 2015 and relate them with potential causes. Several hypotheses were tested: changes in health status, income, diet and socio-economic status. DESIGN: Statistical analysis of trends in anthropometric data: height, weight, BMI and associated Z-scores calculated with the CDC-2000 standard (Centers for Disease Control and Prevention): height-for-age (HAZ), weight-for-age (WAZ) and weight-for-height (WHZ). Trends were fitted with linear regression models and were related with changes in health and socio-economic status. SETTING: Nine nationally representative samples of Senegalese children aged 12-59 months, taken between 1986 and 2017 by Demographic and Health Surveys (DHS). PARTICIPANTS: Children aged 12-59 months. RESULTS: Over the 25 years of investigation, the average height of children increased by +1.88 cm, their average weight by +0.10 kg, but their BMI decreased by -0.53 kg/m2. Corresponding changes expressed in Z-scores were +0.454 in HAZ, +0.109 in WAZ and -0.302 in WHZ. This pattern of decreasing stunting while increasing wasting was correlated with decreasing child mortality, despite small changes in income per capita and in adult heights or BMI. Largest improvements in HAZ were among the lower socio-economic strata, while largest declines in WHZ were among higher socio-economic strata. CONCLUSIONS: Decline in stunting appeared associated primarily with the control of infectious diseases, also responsible for the mortality decline. Increase in wasting was surprising. It appears associated with small changes in income per capita, and therefore in diet, in a context of increasing height.